dmaenegine: edma: allow pause/resume for non-cyclic mode

The 8250_omap serial driver relies on dmaengine_pause() actually
pausing the DMA transfer. Before this patch dmaengine_pause() is
a NOP for non-cylic DMA transfers. This allowed the 8250_omap
driver to read DMA buffers while the DMA was still active,
resulting in lost serial data.

Signed-off-by: John Ogness <john.ogness@linutronix.de>
Acked-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/dma/edma.c

@@ -300,8 +300,7 @@ static int edma_dma_pause(struct dma_chan *chan)
 {
 	struct edma_chan *echan = to_edma_chan(chan);
 
-	/* Pause/Resume only allowed with cyclic mode */
-	if (!echan->edesc || !echan->edesc->cyclic)
+	if (!echan->edesc)
 		return -EINVAL;
 
 	edma_pause(echan->ch_num);
@@ -312,10 +311,6 @@ static int edma_dma_resume(struct dma_chan *chan)
 {
 	struct edma_chan *echan = to_edma_chan(chan);
 
-	/* Pause/Resume only allowed with cyclic mode */
-	if (!echan->edesc->cyclic)
-		return -EINVAL;
-
 	edma_resume(echan->ch_num);
 	return 0;
 }